Suppressing photon detection errors in nondeterministic state preparation

TL;DR

This paper explores methods to reduce photon detection errors in photonic quantum computing by optimizing interferometer parameters, potentially improving fidelity without relying on complex detectors.

Contribution

It introduces an optimization approach for adjusting interferometer angles to suppress detection errors, enhancing gate fidelity in photonic quantum computing.

Findings

Optimized interferometer parameters improve output fidelity.

Error suppression achieved without particle number resolving detectors.

Method maintains success probabilities while reducing errors.

Abstract

Photonic quantum computing has recently emerged as a promising candidate for fault-tolerant quantum computing by photonic qubits. These protocols make use of nondeterministic gates, enabling universal quantum computation. However, the suggested solutions heavily use particle number resolving detectors (PNRDs), which are experimentally hard to realize and are usually biased in practice. We investigate the possibility of suppressing such errors caused by such photodetector imperfections by adjusting the optimal beamsplitter and phaseshifter angles in the interferometer corresponding to nondeterministic gates. Moreover, we devise an optimization method for determining the adjusted angles, which may achieve higher output state fidelities while controlling the success probabilities of the nondeterministic gates.